Tata A M, Biagioni S, Ricci A, Amenta F, Augusti-Tocco G
Dipartimento di Biologia Cellulare e dello Sviluppo, Università La Sapienza, Roma, Italy.
Neurosci Lett. 1995 Apr 21;189(3):139-42. doi: 10.1016/0304-3940(95)11474-b.
The presence and micro-anatomical localization of muscarinic cholinergic receptors were assessed in dorsal root ganglia of chick embryo during development using radioligand binding and immunocytochemical techniques, respectively. The non-selective muscarinic cholinergic receptor radioligand [3H]quinuclidinyl benzilate was specifically bound to sections of chick dorsal root ganglia with a dissociation constant value (Kd) of 0.75 +/- 0.02 nM and a maximum density of binding sites (Bmax) of 7.2 +/- 0.5 fmol/mg tissue. [3H]Quinuclidinyl benzilate binding was partially sensitive to pirenzepine displacement. This suggests that muscarinic cholinergic receptors expressed by dorsal root ganglia of chick embryo at least in part belong to the M1 muscarinic receptor subtype. Immunocytochemical analysis confirmed the presence of muscarinic receptors in the ganglia. These findings suggest that neurons of dorsal root ganglia, which are known to express cholinergic markers such as choline acetyltransferase, acetylcholinesterase and high affinity choline uptake, are also cholinoceptive.
分别采用放射性配体结合和免疫细胞化学技术，对鸡胚发育过程中背根神经节毒蕈碱型胆碱能受体的存在情况和微观解剖定位进行了评估。非选择性毒蕈碱型胆碱能受体放射性配体[3H]喹核醇基苯甲酸酯特异性结合于鸡背根神经节切片，解离常数（Kd）值为0.75±0.02 nM，最大结合位点数（Bmax）为7.2±0.5 fmol/mg组织。[3H]喹核醇基苯甲酸酯结合对哌仑西平置换具有部分敏感性。这表明鸡胚背根神经节表达的毒蕈碱型胆碱能受体至少部分属于M1毒蕈碱受体亚型。免疫细胞化学分析证实了神经节中毒蕈碱受体的存在。这些发现表明，已知表达胆碱能标志物如胆碱乙酰转移酶、乙酰胆碱酯酶和高亲和力胆碱摄取的背根神经节神经元也是胆碱感受性的。
